German Hollow-Charge Ammunition for 75-mm Tank Gun, WWII Tactical and Technical Trends, No. 19: February 25, 1943 (Lone Sentry)

A sketch showing the details of the hollow-charge round for the German 7.5-cm KwK (75-mm tank gun) accompanies this report. The German nomenclature for this ammunition is 7.5-cm Pz. Gr. Patr. 38 KwK.

The round is of the fixed type. The cartridge case and the weight and type of propellant are similar to those for the other types of 75-mm antitank gun ammunition. The shell is fitted with a threaded hemispherical cap into which is screwed a small nose percussion fuze. From the nose fuze, a central tube runs down to a booster which is situated in the base of the shell. This booster consists of a detonator set in penthrite wax, the whole being contained in a perforated container. The bursting charge consists of three blocks of Hexagen (Trimethylene Trinitramine) the front one of which is concave, as shown in the sketch. The blocks are contained in waxed paper and are cemented into the shell.

The operation of the Aufschlag Zunder or percussion fuze (A.Z. 38-type fuze) is simple. The striker is held off the detonator assembly by six centrifugal segments which are surrounded by an expanding spring ring. After the shell has left the gun, centrifugal force causes the clock spring and the safety blocks to open, thus freeing the striker. Upon impact, the striker is driven onto the detonator. The detonation passes down the central tube to initiate the booster. This in turn initiates the bursting charge.

[German Hollow-Charge Ammunition for 75-mm Tank Gun]

The shell is painted white and has black markings. The weight of the shell is 4.5 kilograms, and that of the bursting charge 450 grams.

Comments: This is another instance of the use of hollow-charge ammunition to increase the armor-shattering effect of a gun of comparatively low muzzle velocity. No data is available at this time concerning the performance of this type of projectile against armor at various ranges.